Carton sealing machine

ABSTRACT

A machine for sealing the flap or flaps of a filled carton. The interior surface of each flap is placed in adhering condition by the application of glue or by the heating to sticky condition of a previously applied material. With the flaps in adhering condition, each carton is successively elevated past sloping plates which progressively apply sealing pressure to the flaps. The cartons in stacked relation are held between parallel walls for sufficient time to allow the adhesive to set. The machine is adjustable to receive cartons of different dimensions and is capable of sealing a single flap, two flaps simultaneously or three flaps simultaneously.

Nov. 25, 1975 United States Patent 1 Lee l l CARTON SEALING MACHINE Inventor: Richard G. Lee, 780 Boylston St Primary Emmmer Trm/s Mccehae Boston, Mass. 02199 Apr. 3. 1974 Attorney. Agent. or FirmC. Yardley Chittick [571 ABSTRACT A machine for sealing the flap 0r flaps of a filled car- [221 Filed:

211 Appl. N01457,57l

ton. The interior surface of each flap is placed in ad hering condition by the application of glue or by the [51] Int. Cl. A. t. 8658 51/02 heating to sticky condition of a previously applied ma- Field of Searchm...,............m.i...t..

53/387, 376 terial. With the flaps in adhering condition, each carton is successively elevated past sloping plates which progressively apply sealing pressure to the flaps. The cartons in stacked relation are held between parallel [56] References Cited UNITED STATES PATENTS walls for sufficient time to allow the adhesive to set.

2,095,258 I0/l937 Kimball et al. 53/374 Riccammu The machine is adjustable to receive cartons of differ- Chin ent dimensions and is capable of sealing a single flap. two flaps simultaneously or three flaps simultaneously. FOREIGN PATENTS OR APPLICATIONS 4/l967 Switzerlanduum 53/387 12 (Ilaims- 14 Drawing Figures US. Patent Nov. 25, 1975 Sheetl0f6 3,921,371

US Patent Nov. 25, 1975 Sheet 2 of6 3,921,371

U.S. Patent Nov. 25, 1975 Sheet 3 of6 3,921,371

US. Patent Nov. 25, 1975 Sheet 5 of6 CARTON SEALING MA( HINE FIELD OF THE INVENTION The invention relates generally to means for sealing the end flaps of cardboard cartons after they have been filled with merchandise. When the sealing is complete, the carton is ready for market as a finished unit. In those industries having large production (the cereal industry, for example), automatic machines have been developed which receive the filled cartons from a conveyor and then perform all of the sealing operations without the need of any manual assistance. Such completely automatic sealing machines are. however, very expensive and generally financially out of reach of those whose production is on a more limited scale. In consequence, sealing of cartons in relatively small production industries has been limited to either hand operation or the use of semiautomatic sealing machines which up to the present do not reliably produce properly sealed cartons. It is in this area of limited production and/or limited financial capacity that the present invention finds its principal use.

SUMMARY OF THE INVENTION The present invention contemplates a semiautomatic machine for sealing the end flap or flaps of filled cartons. An operator standing by the machine and adjacent a conveyor, picks up each carton as it arrives on the conveyor, adjusts the unsealed end flaps, places the carton on a track and pushes it into the sealing machine. This is a simple quickly performed operation and requires little skill. With the carton in place in the machine, a switch is actuated by the operator to place the machine in operation. The machine performs automatically the following steps. The inner flap is held substantially vertical and the outer flap is held by the lower portion of a sloping pressure plate located above the flap so that the flaps extends outwardly at a predetermined angle from the vertical. In a preferred form, glue applicators swing up under the outer end flap or flaps applying the adhesive at appropriate locations. The glue applicators then automatically retract and the carton, which at this time is located on an elevator arranged for upward movement by means of an air actuated piston, is moved upwardly between a pair of inwardly sloping pressure applying plates which pressure plates are the same plates that held the flaps firmly in position as the glue was being applied thereto. These spaced plates are pivotally mounted at their lower ends for limited rotation about horizontal axes. Their top portions are closer together than the length of the carton. As each carton proceeds upwardly between these sloping plates, the plates separate to the extent required by the length of the carton while applying pressure to the flap or flaps bringing each outer flap to a vertical position where it is in firm engagement with the inner flap. The carton then continues its upward movement past the top edges of the pivoted plates forming walls and to a position between a pair of fixed parallel vertical plates so spaced that they will hold the carton therebetween and apply a continuous pressure to the flaps for a period long enough for the adhesive to set. In this initial position between the parallel plates, the bottom of the carton will be just above the top edges of the sloping plates permitting the latter under gravity or spring pressure to swing back toward each other to their original positions. The movement of the sloping plates toward each other is limited to positions in which the upper plate edges underlie the opposite ends of the carton thus to limit any subsequent downward movement of the carton from its normal frictionally held position between the parallel pressure plates. The elevator may now be lowered to its original position where it can receive the next carton that will be inserted in the machine by the operator.

When the next carton has been placed in the machine and the operator has again pressed the actuating switch. the glue is again applied to the under sides of the outer flaps while they are held against angular movement by their engagement with the lower parts of the pressure plates after which the next carton, like the preceding carton. is moved by the elevator upwardly past the sloping plates, and in so doing engages the underside of the preceding carton held frictionally by the parallel walls. The preceding carton is then pushed up between the parallel vertical walls for a distance equal to the vertical thickness of the next carton. Possible downward slipping of the cartons from their positions between the parallel walls is prevented by the sloping plates whose upper edges have swung inwardly to be beneath the ends of the last carton.

This series of operations is then continued. Each time a new carton is inserted into the machine and moved upwardly to have its end flaps scaled. the previously inserted cartons are moved upwardly between the parallel pressure walls a distance of one carton. By the time the top carton reaches the top of the parallel pressure walls, the adhesive will be set. The carton may then be removed manually or may be pushed off by an ejector onto a conveyor to be carried to a position where the cartons may be collected for packing in a larger package.

In a second form of the invention, the outer end flaps do not have liquid glue applied thereto but instead the undersides of the flaps are placed in sticky condition through the use of hot air acting on a heat softenable adhesive with which the flaps have been previously coated. The carton is inserted into the machine with the adhesive coated end flap or flaps extending away from the carton at an angle. Each flap is passed over a stream of air heated to a temperature high enough to place the coating in adhering condition. This move ment of the carton past the hot air source is accomplished by the use of an air actuated piston which moves at a controlled speed timed to allow the hot air to bring the adhesive to a softened sticky condition. As the carton leaves the hot air soucre, it is moved forward to a position between the two pivoted plates whose faces are vertical at the areas that engage the end flaps. Thus the outer and inner flaps are placed in immediate engagement while the heated adhesive is in maximum adhering condition. The carton, which is now in position over the elevator, is moved upwardly along the surfaces of the pivoted plates. The upper portions of the plates slope inwardly toward each other and are forced apart as the carton passes thereby. The upward movement of the carton continues until it is delivered to a position between the permanently disposed parallel vertical holding walls. The inwardly sloping upper portions of the pivoted plates fall back into place beneath the opposite edges of the carton so that the carton cannot slip down. With the carton in this secured position. the elevator is then lowered to receive the next carton in the manner just described.

In another modification of the invention. means are provided for the simultaneous sealing of three flaps. This is necessary in those cases where the carton must be top loaded rather than end loaded.

In the sealing machine designed to perform this three flap sealing operation. the loaded carton is manually pushed into the machine with two of the flaps at the opposite ends of the carton and the third flap at the far end. The flaps are held at a proper angle while the glue applicators operate simultaneously to place glue on the underside of each of the three flaps. As soon as this has been accomplished and the glue applicators retracted. the elevator moves upwardly so that the two opposite end flaps are engaged by the sloping pivoted plates heretofore referred to and the third flap is engaged first by a fixed sloping wall and then by a fixed vertical wall. The carton is held in correct position on the elevator by a crosswise extending stop beyond which the carton has been placed by the operator. Two other stops in the form of vertically disposed bars aligned with the crosswise stop are attached to the vertical spaced pressure walls so that when the carton has reached its maximum upward position as determined by the stroke of the elevator, pressure will continue to be applied to all three flaps. As subsequent cartons are inserted in the machine and moved upward with the simultaneous sealing of all three flaps the cartons thereabove are forced upwardly a distance equal to the vertical dimension of one carton. As the finished cartons emerge from the top of the machine they are removed for further handling.

In a further modification, means for adjusting the spacing between the vertical parallel walls and the pivoted sloping plates is provided. This increases the usefulness and productivity of the machine. When cartons of a differing length from the preceding group are to be sealed. the change in spacing between the sloping plates and vertical parallel walls may be made in a matter of seconds by the manual turning of a crank to bring the vertical walls to a spaced position in which they engage the new carton ends with the desired pressure. The operator in making the adjustment holds the new sized carton with the flaps closed but unsealed between the walls with one hand while turning the crank with the other to move the walls toward each other until they bear on the carton with sufficient pressure to insure the proper setting of the glue. At this setting the sloping pivoted plates therebelow and the track leading into the machine. all of which are in fixed relation with the parallel walls. will be in correct location. The elevator position is at a permanent central location which is preferably midway between the walls.

The invention will now be described in more detail with the aid of the accompanying drawings in which:

FIG. 1 is a front perspective view of the machine designed for sealing one or two end flaps.

FIG. 2 is a fragmentary vertical section showing one carton in upper position between the pressure walls and a second carton inserted in the machine in a position over the elevator with the glue applicators in the act of applying glue spots to the under sides of two flaps.

FIG. 3 is similar to FIG. 2 except that the second carton has started its upward movement between the sloping plates.

FIG. 4 is similar to FIGS. 2 and 3 except that the second carton has been moved upwardly to a position part way beyond the upper edges of the pivoted sloping plates and is driving the first carton upward. The sloping plates are in separated positions.

FIG. 5 is a view similar to FIGS. 2, 3 and 4 differing in that it shows the first and second cartons moved to a position above the sloping plates and between the permanently positioned parallel pressure walls. It will be noted in this view that the upper edges of the pivoted sloping plates have returned to positions beneath the opposite edges of the lower carton to prevent the descent of the cartons thereabove.

FIG. 6 is a horizontal section taken approximately on line 66 of FIG. 2 to reduced scale showing the tracks. elevator. two glue tanks. the glue applying fingers therein and air actuating means.

FIG. 7 is a perspective view of the right hand glue tank shown in FIG. 6 in reversed position.

FIG. 8 is a rear fragmentary elevation showing the air actuated means for moving the elevator. the air actuated means for rotating the glue applying fingers.

FIG. 9 is a perspective view of a modification showing semi-automatic loading means and hot air means for rendering adhesive on the end flaps sticky as the carton is moved into the machine by the actuation of an air actuated loader.

FIG. 10 is a plan view taken on the line 10l0 of FIG. ll showing means for simultaneously applying glue to three flaps.

FIG. II is a vertical section taken on line ll-ll of FIG. 10.

FIG. 12 is a perspective view of a fragmentary part of a modification in which the side frames and all related parts may have their spacing quickly changed to accommodate cartons of different dimensions.

FIG. I3 shows the air actuating system.

FIG. 14 shows the electrical system used in hot melt glue machines.

DESCRIPTION OF A PREFERRED EMBODIMENT Referring first to FIGS. I to 7, the machine comprises divided frame portions 2 and 3. The frame portion 2 has front and rear laterally extending flanges of which the front flange is shown at 4 and the rear flange in dotted lines at 5. These flanges are connected by spaced vertical upper and lower walls 12 and 10.

On the other side of the machine the frame portion 3 has relatively short front and rear flanges 11 and 14 which are connected by a lower wall 15 only.

The two frame portions 2 and 3 when in adjusted positions are locked together by a front panel 8 which is bolted to flanges 4 and 11 and by a similar rear panel (not shown) bolted to flanges 5 and 14. Front legs 6 and 7 and corresponding rear legs. not shown. may be used to fasten the machine to an underlying base.

On the right side of the machine a second wall 18 having front and rear flanges 20 and 22 is located above wall 15 in spaced adjusted paralled relation with wall 12. Wall 18 is held in position by two pair of transverse arms. the front pair being shown at 24 and 26. The rear pair being similar but not shown.

Arms 24 and 26 are connected on the left to the flange 4 by bolts 28 and 30 and by bolts 32 and 34 to flange 20 on the right. The rear arms with corresponding rear bolts (not shown) are similar to arms 24 and 26 and are connected to the rear flanges 5 and 22 of walls 12 and I8. When the front bolts 28, 30, 32 and 34 and the corresponding rear bolts are loosened, the wall 18 may be adjusted within limits to a precise spacing from wall 12 and held in such position upon tightening of all of the bolts.

An elevator 36 within the confines of the frame is mounted on a piston rod 38 activated by a vertically disposed air cylinder 39, suitably affixed by upper and lower supports 41 and 43 to the front and rear panels. In front of the elevator and extending outwardly in front of the machine are a pair of spaced guide rails or tracks 40 and 42 having vertical sides 44 and 46 with outwardly flaring portions 48 and 50 at the entering end. The tracks are attached to the walls and 15. The carton whose ends are to be sealed is placed on the tracks 40 and 42 and pushed by hand inwardly along the track extensions 52 and 54 until the carton engages stops 56 and 58 at which position the carton will overlie the elevator 36.

The cross sectional view in FIG. 2 shows a carton 60 whose ends are to be sealed resting in position on tracks 52 and 54 with its flaps 62 and 64 located above glue tanks 66 and 68. These tanks contain a plurality of identical closely spaced generally semicircular fingers 70 and 72 carried by rotable shafts 74 and 76. The fingers are shown in glue applying position against the flaps. The walls 53 and 55 of tracks 52 and 54 hold the inner carton flaps 57 and 59 in vertical position.

When the cartons are initially inserted into the machine, the flaps 62 and 64 are guided by the flaring portions 48 and 50 to pass over the tops of walls 44 and 46 and below the lower edges 78 and 80 of a pair of spaced sloping plates 82 and 84. These plates are supported by front and rear spaced flanges 86 and 88 (see FIG. 1) pivotally mounted for slight swinging movement away from each other on front pivots 90 and 92 affixed to frame flanges 4 and 11 and corresponding pivots (not shown) affixed to flanges 5 and 14. Movement of the plates is limited by stop means 94 and 96 attached to flanges II and 14 and positioned within slots 98 and 100. The upper edges of the sloping plates 82 and 84 indicated at 102 and 104 are closer together than the spaced walls 12 and 18.

When the carton 60 whose ends are to be sealed has been advanced by hand to a position against stops 56 and 58, the carton flaps 62 and 64 which normally would assume a horizontal position will be held in a predetermined angular position as shown in FIG. 2 by their engagement with the lower edges 78 and 80 of the sloping plates 82 and 84.

With the flaps in this position, the glue applying fingers 70 and 72 which were previously immersed in the liquid glue in tanks 66 and 68 are then rotated upwardly so that the tips of the several fingers 70 and 72 deposit a series of closely spaced glue spots on the underside of each of the flaps 62 and 64.

As soon as the glue has been applied, the shafts 74 and 76 are rotated in the reverse direction to reposition the fingers 70 and 72 in the glue. The air cylinder 39 that moves the elevator 36 is then actuated to push the carton 60 upwardly to pass between the pivoted sloping plates 82 and 84. As the upper edges of these plates are closer together than the length of the carton they are forced outwardly as the carton passes thereby, all the while. however. applying a closing force to the flaps 62 and 64 moving the flaps downward to vertical position to press each glued surface against the lower inner flap which up to now has been held in vertical position by the vertical sides 53 and 55 of tracks 52 and 54. The movement of the carton past the sloping plates is shown in FIGS. 3 and 4. The full upward stroke of elevator 36 is sufficient to push the carton to a position between walls 12 and 18 beyond the upper edges 102 and 104 of sloping plates 82 and 84. Once the carton has passed these upper edges 102 and 104, the sloping plates by gravity swing inwardly to their original positions limited by stops 94 and 96, where the top edges I02 and 104 are now located below the opposite ends of the carton. In this way, the carton 60, now in the position indicated at 60 in FIG. 2, is precluded from slipping downwardly from its frictionally held position between walls l2 and 18. The spacing of walls 12 and 18 is precise so that proper pressure is continuously applied against the flaps 62 and 64 for sufficient time for the glue to set properly.

As soon as the first carton has been inserted in the machine and moved from its position shown at 60 in FIG. 2 to position 60', the elevator 36 returns to its down position and the machine is then ready to receive the next carton. The next carton is inserted in the same manner as the first carton as previously described. The glue applying fingers and 72 in the glue tanks are again actuated to apply spots of glue to the undersides of the flaps 62 and 64. The fingers are retracted and the elevator 36 moves the next carton upwardly past the sloping surfaces 82 and 84 to engage the underside of the previous carton then located between the lower portions of walls 12 and 18. The first carton indicated at 60' in FIG. 4 is then pushed up by the second carton 60 a distance equal to the vertical thickness of the second carton. In this position the bottom of carton 60 has passed beyond upper edges I02 and 104 of plates 82 and 84 so that both cartons now will be prevented from moving downwardly because of the engagement of the lower carton 60 with the upper edges 102 and 104.

This series of operations is repeated continuously resulting in a stack of cartons in the machine whose number is limited only by the vertical height of the walls 12 and 18. When an additional carton is placed in the machine and moved upwardly to force the top carton beyond walls I2 and 18, the top carton may then be re moved from the pile by hand or by automatic means to be delivered to a storage or carton packing location.

The glue tanks shown in plan view in FIG. 6 are preferably of greater length than the length of the longest flap to which glue is to be applied. Each of the longitudinal shafts of 74 and 76 of glue tanks 66 and 68 is actuated by a rack and pinion mechanism such as illustrated in FIG. 8. The lower end of rack 1 I0 is attached to a piston rod 112 driven up and down by air cylinder 114. When the rack is driven upwardly, the pinion I16 removably connected to shaft 76, is rotated counterclockwise to swing the leading ends of the fingers 72 in a circular path upwardly and out of the glue in tank 68 to a position in which the ends engage the underside of the flap 64 as illustrated in FIG. 2. The flap 64, it will again be noted, is firmly held against the pressure of the fingers 72 by its engagement with the lower edge of pressure plate 84 so that the glue is properly transferred from the fingers to the flap. A similar rack and pinion simultaneously actuate shaft 74 in the other glue tank 66.

In FIG. 7 is shown a perspective view of one of the glue tanks 66 looking from rear of FIG. 6. Each glue tank is removable from the machine for daily cleaning which is necessary. The shaft 74 has on its end, wings I08 which are adapted to be received in corresponding slots 117 in the side of its operative pinion 116. The flanged ends 110 and 112 are removcably carried by supports in the interior sides of the frame flanges 4, and ll, 14. The tanks are accurately located in the frames by means of notches 109 and 111 in the supporting flanges 110 and 112 which notches cooperate with locating pins 113 and 115 carried by the frames (see FIG. By lifting the tanks a short distance vertically to clear the locating pins and with the wings 108 generally in vertical position so that the said wings can slide out of the cooperating slots 117 in the adjacent side of its operative pinion 116, each tank may readily be removed from the frame for cleaning. The level of the hot or cold liquid glue in the tanks will cover the tips of the fingers when they are in retracted position.

All of the operative parts of the machine are actuated by a compressed air system which is put into operation by manual actuation of a valve under the control of the operator. The sequence of events of the air operated parts is as follows: With the carton in position in the machine. as shown at 60 in FIG. 2, the operator presses a button 106 (see FIG. 1) which opens an air valve allowing air to enter the cylinders that causes rotation of the glue applying fingers. As the piston in this cylinder reaches the end of its stroke. the valve reverses causing the glue fingers to return to their positions in the glue tanks. Promptly thereafter the air cylinder 39 that controls the elevator 36 is actuated, driving the elevator and the carton 60 thereon upwardly past the sloping surfaces of plates 82 and 84 to close the flaps as shown in FIGS. 3, 4 and 5 to place the carton between the vertical walls 12 and 18. The valving is then automatically shifted so that the elevator 36 is caused to descend to its lowermost position at which point the air supply is shut off and the starting control reset to await the insertion of the next carton.

MODIFICATION A modified form of the invention is shown in FIG. 9. The difference in this construction is principally in the means for establishing an adhesive condition on the underside of each of the flaps. In the form previously described the adhesive was applied by gluing fingers in the form of liquid spots of glue. In the modification about to be described, the outer flaps or, if preferred, both the inner and outer flaps earlier in the manufacturing stage of the cartons have had an adhesive applied thereto which adhesive, when unheated. is in a non-sticky stage. By the application of heat, however, the adhesive medium becomes sticky. and if the outer flap is then immediately pressed against the inner flap, the flaps will be secured together and the carton thereby sealed. Examples of suitable adhesive mediums are polyethylene and scalable paraffin wax.

Accordingly, referring to FIG. 9, it will be noted that the construction is generally the same as that shown in FIGS. 1 to 5 except that the glue tanks have been omitted and that hot air heaters 118 and 120 have been positioned in front of panel 8 and a pusher 122 operated by air cylinder 124 is located between the carton supporting tracks 126 and 128. Thus. instead of inserting the carton 130 shown in dotted lines to a position over elevator 36 by hand. the carton is moved into the machine by the operation of pusher 122. The purpose of this arrangement is so that the flaps 62 and 64 held in extended position by walls 136 and 138 will pass over the air heaters 118 and 120 at a constant rate, which rate is determined by the rate at which the hot air will soften the adhesive on the flaps to a sticky condition.

As the carton leaves the heaters 118 and under the influence of pusher 122, the flaps 62 and 64 with the adhesive in scalable condition, are turned to vertical position as they pass under the sloping lower edges 140 and 142 of the pivoted plates 82' and 84'. The faces of plates 82' and 84', being substantially vertical, continue to hold the flaps 62 and 64 against the inner flaps as the carton advances to its position over elevator 36. The lower edges 144 and 146 of plates 82' and 84' are below the bottom of the carton so that pressure against the flaps is applied over their entire areas. Sealing is substantially complete by this time.

The elevator 36 then moves the carton upwardly to engage the inwardly sloping inner portions 132 and 134 of the plates 82' and 8484causing the plates, pivoted at 133 and 135, to separate as the carton 130 passes upward thereby. The plates then fall back to positions with the upper edges of portions 132 and I34 below the carton to prevent subsequent downward movement of the carton from its new position between walls 12 and 18.

The heat softenable adhesive material is well known in the art and the use of hot air heaters to cause the softening is also well understood. As a safety precaution, the voltage that is applied to the electrically heated elements in units 118 and 120 over which the air flows is automatically cut in half when air is not flowing through the heater. If this were not done, the heating elements would burn out prematurely as they are designed to carry full voltage only when air is passing thereover.

Accordingly the air system is so arranged that when pusher 122 commences to move the carton 130 into the machine, air flow through the heater is established and full voltage is on. As soon as the flaps 62 and 64 have passed the air heaters, the air supply to the heaters is automatically shut off and the voltage cut in half. Thus the heaters are always in condition to heat the air adequately as the carton flaps pass thereover but, at the same time, in the lull between the introduction of cartons into the machine, the reduced voltage at that time precludes burning out of the electrical elements.

SECOND MODIFICATION A second modification of the machine is illustrated in FIGS. 10 and 11. The base and sloping walls and the upper parallel walls are the same as in the previous disclosure in FIGS. 1 to 5. The difference in this form resides in means for sealin g simultaneously three flaps on a carton whereas in the construction as shown in FIGS. 1 to 5, the machine is designed to seal one or two flaps only.

Referring to FIG. 10 which is a plan view taken as the line l0-1() of FIG. 11 and to FIG. 11 which is a vertical section taken on the line 1lI1 of FIG. 10. it will be seen that a vertical rear wall 150 having flanges 152 and 154 is secured to the rear flanges 5 and 14 of vertical walls 12 and 18.

Rear wall 150 supports an interior vertical wall 156 whose upper edge is coextensive with the upper edges of walls 12 and 18. The lower edge of wall 156 terminotes at 158 where it connects with an outwardly extending flange 160 which extends through a horizontal aperture 162 through wall 150.

A glue tank 164 similar to tanks 66 and 68 is removably mounted between flanges 152 and 154 at the same level as tanks 66 and 68. A horizontal shaft 166 extends across the tank and carries fingers 168. Means for rotating shaft 166 is provided in the form of the rack and pinion mechanism shown in FIG. 8.

Adjustment means is provided so that the fingers when rotated will apply the spots of glue at preferred positions on the underside of the flap. Glue spots can be applied to appropriate positions on any size flap which flaps range from a size covering the entire end of the carton down to the short or so-callecl economy size flap.

A stop 170 is affixed to elevator 36 at a distance from wall 156 equal to the length of the carton. Upright stops 172 and 174 are fastened to walls 12 and 18 with the same spacing from wall 156 as the stop 170.

When a carton 176 is manually inserted into the machine, it will pass over the transverse stop 170 which is fastened to the upper surface of elevator 36. The lower part of the leading end of the box will engage a stop 178 which extends transversely at the rear of the machine beyond elevator 36. The flap 180 at the rear of the box and the two end flaps 62 and 64 (not shown in FIGS. 10 and 11) will then be positioned above their respective glue tanks 164, 66 and 68.

With the carton in the position shown in FIG. 11, the glue fingers 70, 72 and 168 are simultaneously actuated to apply glue spots to the two flaps over tanks 66 and 68 and to flap 180 over tank 168. The fingers are then retracted and elevator 36 commences to move upward. The end flaps are folded into sealed position by sloping plates 82 and 84 in the manner heretofore explained in relation to FIGS. 1 to 5. The rear flap 180 which had been held in sloping position by flange 160 is also folded to sealing position as the rear of the carton passes upward along wall 156, being held thereagainst by the stop 170 on elevator 36.

When the carton has reached its position between walls 12 and 18 above the top edges 102 and 104 of sloping plates 82 and 84, it will continue to be pressed against wall 156 because of its engagement then with the stops 172 and 174 which are aligned with stop 170.

The three flaps of cartons of different sizes may be sealed by the machine shown in FIGS. 10 and 11 by changing the spacing between walls 12 and 18 in the manner previously explained and by shifting the stops 170, 172 and 174 along elevator 36 and walls 12 and 18 respectively to match the longitudinal dimension of the carton.

THIRD MODIFICATION The object of this modification is to facilitate changing the spacing between the operative parts of the machine to accommodate cartons of different sizes.

On referring to FIG. 12, the walls 182 and 184 represent the lower walls of the frame corresponding to walls 10 and 15 shown in FIG. 1. These walls support in fixed relation the upper structure which in cooperation with the elevator carries out the glue applying and sealing operation. Accordingly if means is provided for varying the spacing between walls 182 and 184, similar changes in spacing will be made with respect to the upper parallel vertical pressure walls, the pivoted sloping plates, the glue tanks and the tracks so that different sized cartons may be processed.

In FIG. 12 such means is illustrated. The walls 182 and 184 are mounted on rollers 186 which are moveable along tracks 188 supported by an underlying base 190. Two strong vertical columns 192 and 194 are secured to base 190. A pair of spaced horizontal beams 196 and 198 with suitable vertical openings therethrough are welded and bolted to columns 192 and 194. The ends of these beams may act as means for supporting a front and rear cover panels such as panel 8 shown in FIG. 1.

Air cylinder 39 located between columns 192 and 194 likewise extends vertically through beam 198 with its piston rod 38 passing freely through beam 196. Channel 200 mounted on rod 38 supports the elevator 36 shown in FIG. 1. Channel 200 is held against rotation by a guide rod 202.

Bearings 204 and 206 mounted in columns 192 and 194 support for rotation transversely extending screws 208 and 210. These screws are right hand threaded at one end and left hand threaded at the other.

For the purpose of explanation it will be assumed that the near ends of screws 208 and 210 at 212 and 214 have left hand Acme threads while the far ends 216 and 218 have right hand Acme threads. These threads are placed in engagement with correspondingly threaded nuts 220, 222, 224 and 226. The nuts are secured in appropriate openings in walls 182 and 184.

A crank 228 with handle 230 is mounted on the near end of screw 208 whereby the screw may be manually turned. Sprockets 232 and 234 of equal size are mounted on screws 208 and 210 adjacent bearings 204 and 206. A chain 236 connects the sprockets.

With the foregoing in mind. it is believed obvious that rotation of crank 228 clockwise will cause walls 182 and 184 to move toward each other and counterclockwise rotation will cause the walls to separate. Since the nuts 220, 222, 224 and 226 are in rigid connection with the walls, the walls will always remain in parallelism regardless of their spacing. Hence all of the structure carried thereabove by wall 182 and 184 will also remain in parallelism as the spacing is varied.

The walls 182 and 184 are shown in FIG. 12 in their positions of maximum spacing. The same walls indicated in dotted lines at 182' and 184' have been shifted to positions of minimum spacing.

Thus when a carton of a new length is to be processed by the machine, the operator will turn crank 228 counterclockwise to separate the walls a distance greater than the length of the carton. Then holding the carton with one hand between the upper parallel pressure walls which are above and integral with walls 182 and 184, the crank will be rotated clockwise to move the parallel pressure walls, such as walls 12 and 18 in FIG. 1, together until they pressure against the folded carton ends with a pressure deemed sufficient to perform a proper holding and sealing operation on the carton flaps.

As soon as the foregoing adjustment has been made. the cartons may be put through the machine to have the flaps sealed in the manner previously explained. Due to the relatively large size of the adjusting screws and the Acme thread configuration, the parts once adjusted remain in stable condition without the need for 5 any locking device.

COMPRESSED AIR ACTUATING SYSTEM The compressed air actuating system is illustrated in FIG. l3. Compressed air is brought to the machine from any convenient source through pipe 240. The air passes through a lubrication and pressure regulating system generally illustrated at 242. The air is led by pipe 244 to a spool valve 246 which is initially in inoperative position. Spool valve 246 is placed in operating condition by the opening of button controlled valve 106 previously referred to. Air then flows through valve 246. pipe 248 and 112 needle valves 250 and 252 to cause simultaneous movement of the pistons 112 in cylinders 114. one of which is shown in more detail in FIG. 8 referred to above. When the pistons 2 move up, they raise the glue fingers that are then residing in the liquid glue in the glue tanks 66, 68. 164 (see FIGS. 2 to 7) to deposit dots of glue on the flaps of the carton that are to be sealed. When the pistons H2 reach the ends of their strokes a cam thereon (not shown) opens valve 254 which shifts the spool of valve 246 shutting off flow of air through pipe 248 and opening flow through pipe 256 and needle valves 266 and 268 to cause the pistons 112 in cylinders 114 to return to their starting positions.

The actuation of valve 254 also causes air to flow through pipe 255 to shift valve 258 to operative position so that air then flows through pipes 259 and 260 and needle valve 270 to cause upward movement of piston 38 in cylinder 39 to which piston is attached the elevator 36 (see FIG. 1). When piston 38 has raised the elevator 36 to the top of its stroke a cam (not shown] on piston rod 38 opens another valve 262. The opening of this valve allows air to flow through needle valve 274 and pipe 263 to shift spool valve 258 to reverse the flow of air so that the air then flows through the pipe 264 and needle valve 272 to drive the piston 38 in cylinder 39 downward to return the elevator 36 to its original position. The needle valves 250, 252, 266. 268, 270 and 272 act to control the speed of the pistons in the several cylinders 114 and 39 on their up and down strokes. Needle valves 274 and 276 act to control the speed of movement of the spools in spool valves 258 and 246 respectively.

The small section enclosed in dotted lines in FIG. 13 and labeled optional delivery chute" is merely to illustrate that means may be provided operating simultaneously with the upward movement of the elevator to remove a finished carton from the top of the pile of boxes as the top-most box emerges at the top of walls [2 and 18.

FIG. 14 illustrates an electrical heating arrangement that is used when the glue in the glue tanks is of the hot melt type. Each glue tank has therein a heater 278 which is connected to the line 280 by a plug 282. One side of the line contains a voltage control 284, an on and off switch 286 and an overload circuit breaker 288. The line 280 is in turn plugged into the main line 290 by plug 292.

If the glue tanks contain cold liquid glue the heaters 278 will be removed therefrom or at least not placed in operation.

From the foregoing it can be seen that the moving parts ofthe machine are actuated solely by compressed air. Once the starting button 106 is pressed all subsequent movements occur automatically in proper sequence. The rate of movement of the various pistons and spool valves is under accurate control through proper setting of the related needle valves.

In the claims when the term llaps" is used it is to be understood that it contemplates both the singular and- /or plural. The specification has made it clear that the machine is capable of sealing a carton with a single flap. two flaps or three flaps.

The sloping plates which preferably are imperforate are preferably set at a greater angle to the vertical when the glue is applied to the flaps from the glue tanks than when the adhesive on the flaps is brought to sticky condition by hot air. In the latter case the pivoted plates are substantially vertical at their lower areas to force the flaps immediately to closed adhering condition.

In the claims it is intended that the term sloping plates" includes plates having a plane surface or a curved or bent surface and set at any desired angle so long as the upper edges of the plates are arranged to move apart as the cartons pass thereby and then to move back to supporting positions below the edges of the carton.

It is further to be understood that the claims are intended to cover the situation in which one of the sloping plates might be fixed instead of pivoted while the other sloping plate is pivoted and capable of moving away from the fixed sloping plate a sufficient distance to allow the carton to pass to its frictionally held position between the parallel walls. In this arrangement, only the pivoted plate would fall back to a position below the elevated carton. This arrangement while workable, is not as satisfactory as the use of two pivoted plates for there is a tendency for the cartons to drop slightly on the unsupported side.

I claim:

1. Means for sealing together the upper and lower end flaps of a carton comprising means for temporarily holding said lower flaps in vertical position and other means for holding said upper flaps in extended position, means for creating an adhesive condition on the under sides of said upper end flaps while the said upper flaps are disposed in said temporary extended condition, opposed pressure plates of which at least one is pivoted on a substantially horizontal axis, the lower edges of said plates comprising the other means for holding said upper flaps in extended position and fixed against upward pivoting movement, said plates also acting to subsequently press said upper flaps against the said lower flaps at the ends of said carton, means for limiting the movement of each pivoted plate toward the other plate, a pair of parallel walls above said plates spaced apart a distance substantially equal to the length of said carton, the distance between the upper edges of said plates being less than the distance between said walls and less than the length of said carton. and an elevator movable vertically between said plates for moving a carton that has been placed on said elevator upward between and past said plates to a position between said walls, the upward movement of said carton causing movement of each said pivoted plate away from the other plate to allow said carton to pass while all the time pressing said upper flaps against said lower flaps, said plates returnable to their original positions to act as means for preventing subsequent downward movement of a carton there above between said walls.

2. The construction set forth in claim 1, said pivoted plates being pivoted at locations below their centers of gravity.

3. The construction set forth in claim 1, the means for creating an adhesive condition on the underside of 13 said end flaps comprising glue tanks and glue applying means movable to positions against said temporarily extended upper flaps.

4. The construction set forth in claim 1, the means for creating an adhesive condition on the underside of said flaps comprising means for blowing hot air against a heat sensitive adhesive previously applied to said flaps.

5. The construction set forth in claim I, said parallel walls and said plates being supported by frames which are mounted on tracks and movable toward or away from each other by manually operable screw threaded means whereby the spacing between said walls and plates may be adjusted to receive cartons of different dimensions.

6. The construction set forth in claim 4, and means for moving a carton into said machine to a position over said elevator and between said plates at a constant rate whereby said flaps will be subjected to said hot air for a predetermined time.

7. The construction set forth in claim 3, and means for simultaneously sealing an upper third flap against a lower third flap located on a side of said carton. said means comprising a stop on said elevator beyond which said carton is positioned, means for holding said upper third flap at an angle away from said carton when said carton is in position on said elevator and resting against said stop, means for applying glue to said upper third flap while glue is being applied to said other upper end flaps, means for moving said upper third flap to and holding it in closed position when said elevator moves said carton upwardly past said plates to its position between said walls.

8. The construction set forth in claim 7, said means for closing and holding said upper third flap in sealing position comprising a third vertical wall at right angles to said parallel walls, and vertically extending abutments on said parallel walls that act to press said carton against said third wall after said elevator and stop thereon have descended.

9. The construction set forth in claim 1, and means for sealing a third upper flap simultaneously with the sealing of said upper end flaps, said last named sealing means comprising means for creating an adhesive condition on the underside of said third upper flap, means on said elevator for holding said carton in longitudinal position thereon, a vertical end wall adapted to hold said third upper flap in closed position as said carton is raised by said elevator and means associated with said parallel walls for pressing said carton against said end wall.

H]. The construction set forth in claim 3, and air actuated means for moving said glue applying means and said elevator in sequence.

11. The construction set forth in claim 1, and tracks for guiding a carton to position over said elevator as it is inserted to its position between said plates.

12. Means for sealing the end flaps of a carton,

said means comprising a frame, a pair of spaced parallel walls carried by said frame and adapted to engage the ends of a carton placed therebetween, an elevator movable vertically for raising a carton to a position between said walls.

a pair of opposed pivoted sloping pressure plates disposed vertically between the level of the down position of said elevator and the lower edges of said parallel walls, the normal position of the upper edges of said pressure plates being closer than the said spaced parallel walls,

means laterally adjacent the down position of said elevator for folding the lower end flaps of an erected but unsealed carton to vertical position as said carton is moved horizontally to a position over said elevator,

other means on opposite sides of said elevator and below said pressure plates for temporarily maintaining said lower end flaps in vertical position prior to upward movement of said elevator.

means for engaging the upper end flaps of said carton as said carton is moved toward said elevator to turn each said upper end flap into an extended downward sloping position,

the lower edges of said pressure plates holding said upper end flaps in said extended position when said carton is located on said elevator,

a tank with glue therein located under each extended upper flap and at least coextensive therewith,

each said glue tank having a longitudinally extending shaft with a plurality of glue applying finger mounted thereon of such dimensions that when said shaft is rotated in one direction the ends of said fingers will rise from said glue and engage the under side of the extended upper flap thereabove,

each said glue tank being removable and having mounting flanges at each end which are carried by supports affixed to said frame, locating means for insuring accurate positioning of each said tank on said frame.

mean for causing simultaneous periodic oscillation of each said shaft and fingers, said mean comprising an air cylinder and piston, a rack extending from said piston, a pinion rotated by said rack, said pinion having its axis aligned with the axis of said shaft, means on the end of said shaft engaging in a slot on the adjacent side of said pinion whereby rotation of said pinion will cause rotation of said shaft,

the engaging means between said shaft and pinion permitting separation thereof by movement of said glue tank in a direction transverse of the shaft axis.

air cylinder actuated means for moving said elevator and carton thereon upward after said fingers have applied glue to said upper flaps,

said pressure plates acting to press said upper flaps against said vertical lower flaps as the carton moves upward toward said parallel walls,

said pressure plates also spreading apart at their upper portions under the influence of the rising carton thereby to permit said carton with its end flaps closed to enter between said parallel walls,

said pressure plates adapted to return to normal position after the carton has passed thereby with the upper edges of said plates beneath said carton. 

1. Means for sealing together the upper and lower end flaps of a carton comprising means for temporarily holding said lower flaps in vertical position and other means for holding said upper flaps in extended position, means for creating an adhesive condition on the under sides of said upper end flaps while the said upper flaps are disposed in said temporary extended condition, opposed pressure plates of which at least one is pivoted on a substantially horizontal axis, the lower edges of said plates comprising the other means for holding said upper flaps in extended position and fixed against upward pivoting movement, said plates also acting to subsequently press said upper flaps against the said lower flaps at the ends of said carton, means for limiting the movement of each pivoted plate toward the other plate, a pair of parallel walls above said plates spaced apart a distance substantially equal to the length of said carton, the distance between the upper edges of said plates being less than the distance between said walls and less than the length of said carton, and an elevator movable vertically between said plates for moving a carton that has been placed on said elevator upward between and past said plates to a position between said walls, the upward movement of said carton causing movement of each said pivoted plate away from the other plate to allow said carton to pass while all the time pressing said upper flaps against said lower flaps, said plates returnable to their original positions to act as means for preventing subsequent downward movement of a carton there above between said walls.
 2. The construction set forth in claim 1, said pivoted plates being pivoted at locations below their centers of gravity.
 3. The construction set forth in claim 1, the means for creating an adhesive condition on the underside of said end flaps comprising glue tanks and glue applying means movable to positions against said temporarily extended upper flaps.
 4. The construction set forth in claim 1, the means for creating an adhesive condition on the underside of said flaps comprising means for blowing hot air against a heat sensitive adhesive previously applied to said flaps.
 5. The construction set forth in claim 1, said parallel walls and said plates being supported by frames which are mounted on tracks and movable toward or away from each other by manually operable screw threaded means whereby the spacing between said walls and plates may be adjusted to receive cartons of different dimensions.
 6. The construction set forth in claim 4, and means for moving a carton into said machine to a position over said elevator and between said plates at a constant rate whereby said flaps will be subjected to said hot air for a predetermined time.
 7. The construction set forth in claim 3, and means for simultaneously sealing an upper third flap against a lower third flap located on a side of said carton, said means comprising a stop on said elevator beyond which said carton is positioned, means for holding said upper third flap at an angle away from said carton when said carton is in position on said elevator and resting against said stop, means for applying glue to said upper third flap while glue is being applied to said other upper end flaps, means for moving said upper third flap to and holding iT in closed position when said elevator moves said carton upwardly past said plates to its position between said walls.
 8. The construction set forth in claim 7, said means for closing and holding said upper third flap in sealing position comprising a third vertical wall at right angles to said parallel walls, and vertically extending abutments on said parallel walls that act to press said carton against said third wall after said elevator and stop thereon have descended.
 9. The construction set forth in claim 1, and means for sealing a third upper flap simultaneously with the sealing of said upper end flaps, said last named sealing means comprising means for creating an adhesive condition on the underside of said third upper flap, means on said elevator for holding said carton in longitudinal position thereon, a vertical end wall adapted to hold said third upper flap in closed position as said carton is raised by said elevator and means associated with said parallel walls for pressing said carton against said end wall.
 10. The construction set forth in claim 3, and air actuated means for moving said glue applying means and said elevator in sequence.
 11. The construction set forth in claim 1, and tracks for guiding a carton to position over said elevator as it is inserted to its position between said plates.
 12. Means for sealing the end flaps of a carton, said means comprising a frame, a pair of spaced parallel walls carried by said frame and adapted to engage the ends of a carton placed therebetween, an elevator movable vertically for raising a carton to a position between said walls, a pair of opposed pivoted sloping pressure plates disposed vertically between the level of the down position of said elevator and the lower edges of said parallel walls, the normal position of the upper edges of said pressure plates being closer than the said spaced parallel walls, means laterally adjacent the down position of said elevator for folding the lower end flaps of an erected but unsealed carton to vertical position as said carton is moved horizontally to a position over said elevator, other means on opposite sides of said elevator and below said pressure plates for temporarily maintaining said lower end flaps in vertical position prior to upward movement of said elevator, means for engaging the upper end flaps of said carton as said carton is moved toward said elevator to turn each said upper end flap into an extended downward sloping position, the lower edges of said pressure plates holding said upper end flaps in said extended position when said carton is located on said elevator, a tank with glue therein located under each extended upper flap and at least coextensive therewith, each said glue tank having a longitudinally extending shaft with a plurality of glue applying finger mounted thereon of such dimensions that when said shaft is rotated in one direction the ends of said fingers will rise from said glue and engage the under side of the extended upper flap thereabove, each said glue tank being removable and having mounting flanges at each end which are carried by supports affixed to said frame, locating means for insuring accurate positioning of each said tank on said frame, mean for causing simultaneous periodic oscillation of each said shaft and fingers, said mean comprising an air cylinder and piston, a rack extending from said piston, a pinion rotated by said rack, said pinion having its axis aligned with the axis of said shaft, means on the end of said shaft engaging in a slot on the adjacent side of said pinion whereby rotation of said pinion will cause rotation of said shaft, the engaging means between said shaft and pinion permitting separation thereof by movement of said glue tank in a direction transverse of the shaft axis, air cylinder actuated means for moving said elevator and carton thereon upward after said fingers have applied glue to said upper flaps, said pressure plates acTing to press said upper flaps against said vertical lower flaps as the carton moves upward toward said parallel walls, said pressure plates also spreading apart at their upper portions under the influence of the rising carton thereby to permit said carton with its end flaps closed to enter between said parallel walls, said pressure plates adapted to return to normal position after the carton has passed thereby with the upper edges of said plates beneath said carton. 